1. Field of the invention
This invention relates generally to exterior panel systems for use in high rise and low rise building construction, and particularly to a self-draining face mount system which is integrated with a building's window system to provide superior protection against moisture penetration, condensation and related water damage.
2. Description of the Prior Art
Generally modern day buildings, and particularly high rise construction, is accomplished using poured concrete flooring slabs which are interspaced vertically and supported by means of a steel beam and concrete framework. The exterior of the buildings is usually comprised of a combination of solid facing material and a window system which together form the external wall structure.
Window systems are placed between the concrete flooring slabs using a variety of installation techniques. Many of these techniques involve covering the end of the flooring slab and any internal wall structure with some type of weather resistant panel, securing the window in place and then sealing any resulting joints with a weather resistant sealant such as exterior caulking to prevent moisture entry and the resultant damage typically caused thereby.
All exterior grade weather resistant sealants currently employed breakdown over time due to curing and drying out of the compound itself, due to stress related to building deflection and movement, and also due to exposure to the elements including exposure to ultra violet radiation. This breakdown causes the sealant to lose its effectiveness in preventing moisture entry into the interior of the wall system or further into the interior of the building.
One present attempt to solve the problem is to remove the sealant once it has broken down and replace it with new material. This requires substantial time and expense and damage can still result if this procedure is not performed on a timely basis.
Other methods involve modifications to the physical design of a panel system or window system in an attempt to prevent moisture that does penetrate the sealant from entering the interior wall system. These methods typically employ designs that minimize the number of joints that must be sealed. For example, one solution provides windows with frames that are enlarged so as to cover the end of an adjacent flooring slab, and which continue until they meet the frame of an adjacent window. This design reduces the number of joints between adjacent windows from two to one.
Another problem with the existing efforts is that the metal panels used to cover the end of the flooring slab and any internal wall structure have typically been made and fastened to a building structure in a way which allows outdoor temperatures to be conveyed to the interior of the wall system, thereby creating an area at which condensation can form, damaging the adjacent interior room finish.
To date none of the attempted solutions has been entirely satisfactory in preventing moisture penetration to the interior wall system once the sealant has broken down.